Lint & small changes

server-rs/src/aggregation.rs

@@ -1,6 +1,13 @@
 use crate::consts::NAN_U16;
 use crate::data::QuantRef;
 
+/// Optional per-enum-value distribution tracking for a single feature.
+/// Counts how many rows have each enum value (by raw u16 index).
+pub struct EnumDist {
+    pub feat_idx: usize,
+    pub counts: Box<[u32]>,
+}
+
 /// Per-cell accumulator for aggregating features (min/max/sum/count).
 /// Uses Box<[T]> instead of Vec<T> to avoid storing capacity (saves 8 bytes per field per cell).
 /// Shared by hexagon and postcode aggregation routes.
@@ -10,16 +17,26 @@ pub struct Aggregator {
     pub maxs: Box<[f32]>,
     pub sums: Box<[f64]>,
     pub feat_counts: Box<[u32]>,
+    /// Optional: per-value counts for a single enum feature (for pie chart visualization).
+    pub enum_dist: Option<EnumDist>,
 }
 
+/// Configuration for enum distribution tracking, passed to Aggregator::new.
+/// (feature_index, number_of_enum_values)
+pub type EnumDistConfig = Option<(usize, usize)>;
+
 impl Aggregator {
-    pub fn new(num_features: usize) -> Self {
+    pub fn new(num_features: usize, enum_dist_config: EnumDistConfig) -> Self {
         Aggregator {
             count: 0,
             mins: vec![f32::INFINITY; num_features].into_boxed_slice(),
             maxs: vec![f32::NEG_INFINITY; num_features].into_boxed_slice(),
             sums: vec![0.0f64; num_features].into_boxed_slice(),
             feat_counts: vec![0u32; num_features].into_boxed_slice(),
+            enum_dist: enum_dist_config.map(|(feat_idx, num_values)| EnumDist {
+                feat_idx,
+                counts: vec![0u32; num_values].into_boxed_slice(),
+            }),
         }
     }
 
@@ -50,6 +67,17 @@ impl Aggregator {
                 self.feat_counts[feat_index] += 1;
             }
         }
+        // Enum distribution: single branch per row (not per feature).
+        // Uses raw u16 directly — enum features are stored as u16 indices.
+        if let Some(ref mut ed) = self.enum_dist {
+            let raw = row_slice[ed.feat_idx];
+            if raw != NAN_U16 {
+                let idx = raw as usize;
+                if idx < ed.counts.len() {
+                    ed.counts[idx] += 1;
+                }
+            }
+        }
     }
 
     /// Merge another aggregator's results into this one.
@@ -67,6 +95,12 @@ impl Aggregator {
                 self.feat_counts[i] += other.feat_counts[i];
             }
         }
+        // Merge enum distribution counts
+        if let (Some(ref mut mine), Some(ref theirs)) = (&mut self.enum_dist, &other.enum_dist) {
+            for (m, t) in mine.counts.iter_mut().zip(theirs.counts.iter()) {
+                *m += t;
+            }
+        }
     }
 
     /// Add a row, only aggregating the features at the given indices.
@@ -95,5 +129,15 @@ impl Aggregator {
                 self.feat_counts[feat_index] += 1;
             }
         }
+        // Enum distribution (same raw u16 approach)
+        if let Some(ref mut ed) = self.enum_dist {
+            let raw = feature_data[base + ed.feat_idx];
+            if raw != NAN_U16 {
+                let idx = raw as usize;
+                if idx < ed.counts.len() {
+                    ed.counts[idx] += 1;
+                }
+            }
+        }
     }
 }

server-rs/src/parsing/fields.rs

@@ -31,6 +31,33 @@ pub fn parse_field_indices(
     Ok(Some(indices))
 }
 
+/// Parse an optional `?enum_dist=` query param into (feature_index, num_values) for
+/// per-value distribution counting. Returns None if not requested.
+/// Returns 400 if the feature name is unknown or not an enum feature.
+pub fn parse_enum_dist(
+    enum_dist: Option<&str>,
+    name_to_index: &FxHashMap<String, usize>,
+    enum_values: &FxHashMap<usize, Vec<String>>,
+) -> Result<Option<(usize, usize)>, (StatusCode, String)> {
+    let Some(name) = enum_dist else {
+        return Ok(None);
+    };
+    let name = name.trim();
+    if name.is_empty() {
+        return Ok(None);
+    }
+    let &feat_idx = name_to_index
+        .get(name)
+        .ok_or_else(|| (StatusCode::BAD_REQUEST, format!("Unknown feature: {name}")))?;
+    let values = enum_values.get(&feat_idx).ok_or_else(|| {
+        (
+            StatusCode::BAD_REQUEST,
+            format!("Feature is not an enum: {name}"),
+        )
+    })?;
+    Ok(Some((feat_idx, values.len())))
+}
+
 /// Parse an optional `?fields=` query param into a HashSet for stats filtering.
 /// Returns `(fields_specified, field_set)`.
 pub fn parse_field_set(fields: Option<&str>) -> (bool, HashSet<String>) {

server-rs/src/parsing/filters.rs

@@ -605,10 +605,14 @@ mod tests {
         //   row 3: price=600, area=300 → fails both
         let tq = test_quant(2, 2);
         let feature_data = vec![
-            tq.encode(0, 150.0), tq.encode(1, 100.0), // row 0
-            tq.encode(0, 600.0), tq.encode(1, 100.0), // row 1
-            tq.encode(0, 150.0), tq.encode(1, 300.0), // row 2
-            tq.encode(0, 600.0), tq.encode(1, 300.0), // row 3
+            tq.encode(0, 150.0),
+            tq.encode(1, 100.0), // row 0
+            tq.encode(0, 600.0),
+            tq.encode(1, 100.0), // row 1
+            tq.encode(0, 150.0),
+            tq.encode(1, 300.0), // row 2
+            tq.encode(0, 600.0),
+            tq.encode(1, 300.0), // row 3
         ];
         let filters = vec![
             ParsedFilter {
@@ -626,10 +630,10 @@ mod tests {
         let (total, impacts) =
             count_filter_impacts(&filters, &[], &feature_data, 2, (0..4u32).into_iter());
 
-        assert_eq!(total, 1);       // only row 0 passes
-        assert_eq!(impacts[0], 1);  // row 1 fails price only
-        assert_eq!(impacts[1], 1);  // row 2 fails area only
-        // row 3 fails both → not counted
+        assert_eq!(total, 1); // only row 0 passes
+        assert_eq!(impacts[0], 1); // row 1 fails price only
+        assert_eq!(impacts[1], 1); // row 2 fails area only
+                                   // row 3 fails both → not counted
     }
 
     #[test]
@@ -640,9 +644,12 @@ mod tests {
         //   row 2: price=600, type=0(A) → fails numeric only
         let tq = test_quant(2, 1);
         let feature_data = vec![
-            tq.encode(0, 150.0), 0u16,  // row 0
-            tq.encode(0, 150.0), 2u16,  // row 1
-            tq.encode(0, 600.0), 0u16,  // row 2
+            tq.encode(0, 150.0),
+            0u16, // row 0
+            tq.encode(0, 150.0),
+            2u16, // row 1
+            tq.encode(0, 600.0),
+            0u16, // row 2
         ];
         let num_filters = vec![ParsedFilter {
             feat_idx: 0,
@@ -662,9 +669,9 @@ mod tests {
             (0..3u32).into_iter(),
         );
 
-        assert_eq!(total, 1);       // row 0
-        assert_eq!(impacts[0], 1);  // row 2 fails numeric only → impacts[0]
-        assert_eq!(impacts[1], 1);  // row 1 fails enum only → impacts[1]
+        assert_eq!(total, 1); // row 0
+        assert_eq!(impacts[0], 1); // row 2 fails numeric only → impacts[0]
+        assert_eq!(impacts[1], 1); // row 1 fails enum only → impacts[1]
     }
 
     #[test]

server-rs/src/routes/ai_filters.rs

@@ -946,10 +946,7 @@ pub async fn post_ai_filters(
 
         // Auto-inject Listing status filter for historical mode
         if let Value::Object(ref mut map) = filters {
-            map.insert(
-                "Listing status".to_string(),
-                json!(["Historical sale"]),
-            );
+            map.insert("Listing status".to_string(), json!(["Historical sale"]));
         }
 
         // Count matching properties and refine if too restrictive